I'm cheap so I'm using the FREE sim from www.marksfiles.net

http://www.marksfiles.net/HeliSimRC/index.htm

You'll need some sort of USB connector for your transmitter to connect to the PC, mine cost about $7 for my Futaba 7C transmitter. Iused a GWScable similar to this:

http://www.rctoys.com/rc-toys-and-pa...RS-WIRING.html

If you like the Heli Sim, you can donate to the software programmer who wrote it via Paypal. I know I've saved hundreds of $$$ in crash repairs alone, and even though it's not as fancy as the other name brand sims, it does have a lot of features (wind, heli parameter like throttle/pitch curve adjustments, etc). It got me used to hovering nose-in, forward flight, inverted flight (it has an idle-up feature), etc.

Heck, it's FREE! Why spend $$$ until you need to?

Mark